British intelligence agents determined to wreck the peace process were behind the covert spying uncovered last week, it was claimed.

The party, which demanded answers from the Government, said the device was planted in the attic of a flat in the Andersonstown district of west Belfast.A woman who works in Mr Adams's constituency offices lives there.

Sinn Fein sources said the second bug was detected at the party's Connolly House premises last night.

"We got people to sweep a lot of party offices after the first one was found."